Monitoring server, resolution server, request device, and node selection method

ABSTRACT

Embodiments of the present application provide a monitoring server, a resolution server, a request device, and a node selection method. The monitoring server in the present application includes a receiver, a processor, and a transmitter. The receiver is configured to receive a selection request message sent by the resolution server; the processor is configured to generate a first source node suggestion table according to the selection request message and a source node selection table; and the transmitter is configured to send the first source node suggestion table to the resolution server, so that the resolution server generates a second source node suggestion table according to the first source node suggestion table and sends the second source node suggestion table to the request device, and the request device selects a source node according to the second source node suggestion table.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2014/074802, filed on Apr. 4, 2014, the disclosure of which ishereby incorporated by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present application relate to the communicationstechnologies, and in particular, to a monitoring server, a resolutionserver, a request device, and a node selection method.

BACKGROUND

Information-Centric Networking (ICN) changes content and terminallocations in a current end-to-end communication mechanism of theInternet to be no longer correlated, and provides services such asstorage and multi-party communication by using a publish/subscribeparadigm (Publish/Subscribe Paradigm). The ICN has a structure extremelysimilar to that of a Transmission Control Protocol (TCP)/InternetProtocol (IP) network, where both structures are of a sandglass model,and a difference only lies in that, in the structure of the ICN, an IPis replaced with a content chunk.

Currently, many methods or engineering application projects arespringing up in terms of study on the ICN, which can be mainly dividedinto two major branches: the European branch and the US branch. InEurope, there are mainly a Publish-Subscribe Internet Technology(PURSUIT), a Publish-Subscribe Internet Routing Paradigm (PSIRP), aNetwork of Information (NetInf), Scalable and Adaptive InternetSolutions (SAIL), and Content-Oriented Networking: a New Experience forContent Transfer (CONNECT). In the United States, there are mainlyContent Centric Networking/Named Data Networking (CCN/NDN) and a DataOriented Network Architecture (DONA).

In these existing ICN technologies, when wanting to receive a requiredinformation object (IO), a subscriber sends an IO request to aresolution server (RS) by using a client. After receiving the IOrequest, the RS generates a list having identifier information of atleast one data source node according to location information, statusinformation, load information, and the like of a reference node, andfeeds back the list to the Client. After receiving the information list,the Client selects one node according to identifier information of thedata source nodes and requests specific content of the IO.

In the prior art, reference information, which is fed back by the RS, ofan identifier of a data source node is extremely limited. However, someservices such as a video service have a relatively high bandwidthrequirement. A data transmission rate between a requester and a sourcenode directly affects service experience of a user. Therefore, in theICN network, a data source node that is selected according to thereference information such as location information, status information,and load information for a service request having a relatively highbandwidth requirement may be not a most suitable node. Consequently, avideo “freeze” phenomenon occurs due to a relatively low transmissionrate between a requester and the selected source node.

SUMMARY

Embodiments of the present application provide a monitoring server, aresolution server, a request device, and a node selection method, toresolve a problem in the prior art that a “freeze” phenomenon may occurin a service having a relatively high bandwidth requirement.

According to a first aspect, an embodiment of the present applicationprovides a monitoring server, including:

a receiver, a processor, and a transmitter, where the receiver, theprocessor, and the transmitter are sequentially connected, and thereceiver and the transmitter are connected to a resolution server;

the receiver is configured to receive a selection request message sentby the resolution server, where the selection request informationincludes an access network identifier of a request device;

the processor is configured to generate a first source node suggestiontable according to the selection request message and a source nodeselection table, where the source node selection table includes atransmission rate between the request device and at least one sourcenode, and the first source node suggestion table includes an identifierof the at least one source node; and

the transmitter is configured to send the first source node suggestiontable to the resolution server, so that the resolution server generatesa second source node suggestion table according to the first source nodesuggestion table and reference information of the at least one sourcenode and sends the second source node suggestion table to the requestdevice, and the request device selects a source node according to thesecond source node suggestion table, where the reference informationincludes location information, status information, and load information,and a quantity of identifiers of source nodes in the second source nodesuggestion table is less than or equal to a quantity of identifiers ofsource nodes in the first source node suggestion table.

According to the first aspect, in a first possible implementation mannerof the first aspect, the access network identifier of the request deviceis obtained by the resolution server according to a received filerequest message sent by the request device.

According to the first possible implementation manner of the firstaspect, in a second possible implementation manner, the selectionrequest message further includes a source node identifier table, and thesource node identifier table is a source node identifier table that isgenerated after the resolution server performs querying according to anidentifier of a requested file and that has the requested file, wherethe identifier of the requested file is obtained by the resolutionserver according to the file request message.

According to any one of the first aspect, or the first or the secondpossible implementation manner of the first aspect, in a third possibleimplementation manner, the processor is further configured to query,according to the access network identifier of the request device, thesource node selection table for a transmission rate between the accessnetwork identifier of the request device and each source node, andgenerate the first source node suggestion table according to thetransmission rate between the access network identifier of the requestdevice and each source node.

According to the third possible implementation manner of the firstaspect, in a fourth possible implementation manner, the processor isfurther configured to query, according to the access network identifierof the request device and by means of longest prefix match, the sourcenode selection table for the transmission rate between the accessnetwork identifier of the request device and each source node.

According to any one of the first aspect, or the first to the fourthpossible implementation manners of the first aspect, in a fifth possibleimplementation manner, the receiver is further connected to the requestdevice and the selected source node;

the receiver is further configured to receive a transmission rate thatis between the request device and the selected source node and that isreported by the request device or the selected source node; and

the processor is further configured to update the source node selectiontable according to the transmission rate between the request device andthe selected source node.

According to the fifth possible implementation manner of the firstaspect, in a sixth possible implementation manner, the receiver isfurther configured to receive the transmission rate that is between therequest device and the selected source node and that is reported by therequest device or the selected source node according to a preset time ora preset period.

According to a second aspect, an embodiment of the present applicationprovides a resolution server, including: a transmitter, a receiver, anda processor, where the receiver and the processor are connected to thetransmitter; the transmitter and the receiver are separately connectedto a monitoring server; and the transmitter is further connected to arequest device;

the transmitter is configured to send a selection request message to themonitoring server, so that the monitoring server generates a firstsource node suggestion table according to the selection request messageand a source node selection table, where the selection request messageincludes an access network identifier of the request device, the sourcenode selection table includes a transmission rate between the requestdevice and at least one source node, and the first source nodesuggestion table includes an identifier of the at least one source node;

the receiver is configured to receive the first source node suggestiontable sent by the monitoring server;

the processor is configured to generate a second source node suggestiontable according to the first source node suggestion table and referenceinformation of the at least one source node, where the referenceinformation includes location information, status information, and loadinformation, and a quantity of identifiers of source nodes in the secondsource node suggestion table is less than or equal to a quantity ofidentifiers of source nodes in the first source node suggestion table;and

the transmitter is further configured to send the second source nodesuggestion table to the request device, so that the request deviceselects a source node according to the second source node suggestiontable.

According to the second aspect, in a first possible implementationmanner of the second aspect, the receiver is further connected to therequest device; and

the receiver is further configured to: before the transmitter sends theselection request message to the monitoring server, receive a filerequest message sent by the request device, where the file requestmessage includes an identifier of a requested file and the accessnetwork identifier of the request device.

According to the first possible implementation manner of the secondaspect, in a second possible implementation manner, the processor isfurther configured to: before the transmitter sends the selectionrequest message to the monitoring server, perform querying according tothe identifier of the requested file and generate a source nodeidentifier table having the requested file, where correspondingly, theselection request message further includes the source node identifiertable.

According to any one of the second aspect, or the first or the secondpossible implementation manner of the second aspect, in a third possibleimplementation manner, the transmitter is further configured to send thesecond source node suggestion table to the request device by usingmetadata.

According to a third aspect, an embodiment of the present applicationfurther provides a request device, including a receiver, a processor,and a transmitter, where the receiver is connected to the processor, andthe receiver is further connected to a resolution server;

the receiver is configured to receive a second source node suggestiontable sent by the resolution server, where the second source nodesuggestion table is generated by the resolution server according to afirst source node suggestion table and reference information of at leastone source node; the reference information includes locationinformation, status information, and load information; the first sourcenode suggestion table is generated by the monitoring server according toa selection request message that is sent by the resolution server and asource node selection table; the selection request message includes anaccess network identifier of the request device; the source nodeselection table includes a transmission rate between the request deviceand the at least one source node; the first source node suggestion tableincludes an identifier of the at least one source node; and a quantityof identifiers of source nodes in the second source node suggestiontable is less than or equal to a quantity of identifiers of source nodesin the first source node suggestion table; and

the processor is configured to select a source node according to thesecond source node suggestion table.

According to the third aspect, in a first possible implementation mannerof the third aspect, the transmitter is configured to send a filerequest message to the resolution server before the receiver receivesthe source node suggestion table sent by the resolution server, wherethe file request message includes an identifier of a requested file andthe access network identifier of the request device.

According to the third aspect or the first possible implementationmanner of the third aspect, in a second possible implementation manner,the receiver is further configured to receive the second source nodesuggestion table that is sent by the resolution server by usingmetadata.

According to any one of the third aspect, or the first or the secondpossible implementation manner of the third aspect, in a third possibleimplementation manner, the processor is further configured to: if thesecond source node suggestion table includes identifiers of at least twosource nodes, select one source node from the source node suggestiontable according to priorities of the at least two source nodes, andrequest the requested file from the source node; or separately request,from the at least two source nodes, content fragments of the requestedfile according to priorities of the at least two source nodes, to obtainthe requested file.

According to any one of the third aspect, or the first to the thirdpossible implementation manners of the third aspect, in a fourthpossible implementation manner, the transmitter is further connected tothe monitoring server; and

the transmitter is further configured to report a transmission ratebetween the request device and the selected source node to themonitoring server, so that the monitoring server updates the source nodeselection table.

According to the fourth possible implementation manner of the thirdaspect, in a fifth possible implementation manner, the transmitter isfurther configured to report the transmission rate between the requestdevice and the selected source node to the monitoring server accordingto a preset time or a preset period, so that the monitoring serverupdates the source node selection table.

According to a fourth aspect, an embodiment of the present applicationfurther provides a node selection method, including:

receiving a selection request message sent by a resolution server, wherethe selection request includes an access network identifier of a requestdevice;

generating a first source node suggestion table according to theselection request message and a source node selection table, where thesource node selection table includes a transmission rate between therequest device and at least one source node, and the first source nodesuggestion table includes an identifier of the at least one source node;and

sending the first source node suggestion table to the resolution server,so that the resolution server generates a second source node suggestiontable according to the first source node suggestion table and referenceinformation of the at least one source node and sends the second sourcenode suggestion table to the request device, and the request deviceselects a source node according to the second source node suggestiontable, where the reference information includes location information,status information, and load information, and a quantity of identifiersof source nodes in the second source node suggestion table is less thanor equal to a quantity of identifiers of source nodes in the firstsource node suggestion table.

According to the fourth aspect, in a first possible implementationmanner of the fourth aspect, the access network identifier of therequest device is obtained by the resolution server according to areceived file request message sent by the request device.

According to the first possible implementation manner of the fourthaspect, in a second possible implementation manner, the selectionrequest message further includes a source node identifier table, and thesource node identifier table is a source node identifier table that isgenerated after the resolution server performs querying according to anidentifier of a requested file and that has the requested file, wherethe identifier of the requested file is obtained by the resolutionserver according to the file request message.

According to any one of the fourth aspect, or the first or the secondpossible implementation manner of the fourth aspect, in a third possibleimplementation manner, the generating a first source node suggestiontable according to the selection request message and a source nodeselection table includes:

querying, according to the access network identifier of the requestdevice, the source node selection table for a transmission rate betweenthe access network identifier of the request device and each sourcenode; and

generating the first source node suggestion table according to thetransmission rate between the access network identifier of the requestdevice and each source node.

According to the third possible implementation manner of the fourthaspect, in a fourth possible implementation manner, the querying,according to the access network identifier of the request device, thesource node selection table for a transmission rate between the accessnetwork identifier of the request device and each source node includes:

querying, according to the access network identifier of the requestdevice and by means of longest prefix match, the source node selectiontable for the transmission rate between the access network identifier ofthe request device and each source node.

According to any one of the fourth aspect, or the first to the fourthpossible implementation manners of the fourth aspect, in a fifthpossible implementation manner, the method further includes:

receiving a transmission rate that is between the request device and theselected source node and that is reported by the request device or theselected source node, and updating the source node selection table.

According to the fifth possible implementation manner of the fourthaspect, in a sixth possible implementation manner, the receiving atransmission rate that is between the request device and the selectedsource node and that is reported by the request device or the selectedsource node, and updating the source node selection table includes:

receiving the transmission rate that is between the request device andthe selected source node and that is reported by the request device orthe selected source node according to a preset time or a preset period,and updating the source node selection table.

According to a fifth aspect, an embodiment of the present applicationfurther provides a node selection method, including:

sending a selection request message to a monitoring server, so that themonitoring server generates a first source node suggestion tableaccording to the selection request message and a source node selectiontable, where the selection request includes an access network identifierof a request device, the source node selection table includes atransmission rate between the request device and at least one sourcenode, and the first source node suggestion table includes an identifierof the at least one source node;

receiving the first source node suggestion table sent by the monitoringserver;

generating a second source node suggestion table according to the firstsource node suggestion table and reference information of the at leastone source node, where the reference information includes locationinformation, status information, and load information, and a quantity ofidentifiers of source nodes in the second source node suggestion tableis less than or equal to a quantity of identifiers of source nodes inthe first source node suggestion table; and

sending the second source node suggestion table to the request device,so that the request device selects a source node according to the secondsource node suggestion table.

According to the fifth aspect, in a first possible implementation mannerof the fifth aspect, before the sending a selection request message to amonitoring server, the method further includes:

receiving a file request message sent by the request device, where thefile request message includes an identifier of a requested file and theaccess network identifier of the request device.

According to the first possible implementation manner of the fifthaspect, in a second possible implementation manner, before the sending aselection request message to a monitoring server, the method furtherincludes:

performing querying according to the identifier of the requested fileand generating a source node identifier table having the requested file,where correspondingly, the selection request message further includesthe source node identifier table.

According to any one of the fifth aspect, or the first or the secondpossible implementation manner of the fifth aspect, in a third possibleimplementation manner, the sending the second source node suggestiontable to the request device includes:

sending the second source node suggestion table to the request device byusing metadata.

According to a sixth aspect, an embodiment of the present applicationfurther provides a node selection method, including:

receiving a second source node suggestion table sent by a resolutionserver, where the second source node suggestion table is generated bythe resolution server according to a first source node suggestion tableand reference information of at least one source node; the referenceinformation includes location information, status information, and loadinformation; the first source node suggestion table is generated by themonitoring server according to a selection request message that is sentby the resolution server and a source node selection table; theselection request includes an access network identifier of the requestdevice; the source node selection table includes a transmission ratebetween the request device and the at least one source node; the firstsource node suggestion table includes an identifier of the at least onesource node; and a quantity of identifiers of source nodes in the secondsource node suggestion table is less than or equal to a quantity ofidentifiers of source nodes in the first source node suggestion table;and

selecting a source node according to the second source node suggestiontable.

According to the sixth aspect, in a first possible implementation mannerof the sixth aspect, before the receiving a second source nodesuggestion table sent by a resolution server, the method furtherincludes:

sending a file request message to the resolution server, where the filerequest message includes an identifier of a requested file and theaccess network identifier of the request device.

According to the sixth aspect or the first possible implementationmanner of the sixth aspect, in a second possible implementation manner,the receiving a second source node suggestion table sent by a resolutionserver includes:

receiving the second source node suggestion table that is sent by theresolution server by using metadata.

According to any one of the sixth aspect, or the first or the secondpossible implementation manner of the sixth aspect, in a third possibleimplementation manner, the selecting a source node according to thesecond source node suggestion table includes:

if the second source node suggestion table includes identifiers of atleast two source nodes, selecting one source node from the source nodesuggestion table according to priorities of the at least two sourcenodes, and requesting the requested file from the source node; or

separately requesting, from the at least two source nodes, contentfragments of the requested file according to priorities of the at leasttwo source nodes, to obtain the requested file.

According to any one of the sixth aspect, or the first to the thirdpossible implementation manners of the sixth aspect, in a fourthpossible implementation manner, the method further includes:

reporting a transmission rate between the request device and theselected source node to the monitoring server, so that the monitoringserver updates the source node selection table.

According to the fourth possible implementation manner of the sixthaspect, in a fifth possible implementation manner, the reporting atransmission rate between the request device and the selected sourcenode to the monitoring server and updating the source node selectiontable includes:

reporting the transmission rate between the request device and theselected source node to the monitoring server according to a preset timeor a preset period, so that the monitoring server updates the sourcenode selection table.

According to the monitoring server, the resolution server, the requestdevice, and the node selection method provided in the embodiments of thepresent application, the monitoring server generates a first source nodesuggestion table according to a selection request message sent by theresolution server and a source node selection table, and feeds back thefirst source node suggestion table to the resolution server; theresolution server processes the first source node suggestion table togenerate a second source node suggestion table and sends the secondsource node suggestion table to the request device. Because the firstsource node suggestion table is generated according to a transmissionrate between the request device and at least one source node, so thatthe request device selects a source node that better meets atransmission bandwidth requirement of a service requested by the requestdevice, so as to meet a transmission requirement of a high-bandwidthservice and avoid a “freeze” phenomenon caused by a low transmissionrate.

BRIEF DESCRIPTION OF DRAWINGS

To describe the technical solutions in the embodiments of the presentapplication more clearly, the following briefly describes theaccompanying drawings required for describing the embodiments.Apparently, the accompanying drawings in the following description showsome embodiments of the present application, and persons of ordinaryskill in the art may still derive other drawings from these accompanyingdrawings without creative efforts.

FIG. 1 is a schematic structural diagram of a monitoring serveraccording to Embodiment 1 of the present application;

FIG. 2 is a schematic structural diagram of a monitoring serveraccording to Embodiment 3 of the present application;

FIG. 3 is a schematic structural diagram of a resolution serveraccording to Embodiment of the present application;

FIG. 4 is a schematic structural diagram of a resolution serveraccording to Embodiment 7 of the present application;

FIG. 5 is a schematic structural diagram of a request device accordingto Embodiment 8 of the present application;

FIG. 6 is a flowchart of a node selection method according to Embodiment9 of the present application; and

FIG. 7 is a flowchart of a node selection method according to Embodiment10 of the present application.

DESCRIPTION OF EMBODIMENTS

To make the objectives, technical solutions, and advantages of theembodiments of the present application clearer, the following clearlydescribes the technical solutions in the embodiments of the presentapplication with reference to the accompanying drawings in theembodiments of the present application. Apparently, the describedembodiments are some but not all of the embodiments of the presentapplication. All other embodiments obtained by persons of ordinary skillin the art based on the embodiments of the present application withoutcreative efforts shall fall within the protection scope of the presentapplication.

Embodiment 1

FIG. 1 is a schematic structural diagram of a monitoring serveraccording to Embodiment 1 of the present application. The monitoringserver in this embodiment is located in an ICN network communicationssystem, and may exist as a device independent of a resolution server inthe ICN network, or may be configured in the resolution server. Themonitoring server may be a network monitoring server (NMS) and isgenerally implemented in a hardware manner or in a hardware and softwarecombined manner. As shown in FIG. 1, a monitoring server 100 includes areceiver 101, a processor 102, and a transmitter 103. The receiver 101,the processor 102, and the transmitter 103 are sequentially connected.The receiver 101 and the transmitter 103 are connected to a resolutionserver 104.

The receiver 101 is configured to receive a selection request messagesent by the resolution server 104, where the selection request messageincludes an access network identifier of a request device.

The selection request message may be specifically a source nodeidentifier selection request (Source ID Selection Request) message. Theselection request message may be a request message that is sent by theresolution server 104 according to a preset request device and that isused for selecting a data source node for the preset request device, ormay be a selection message that is sent according to an order ofpriorities of multiple preset request devices and that is used forselecting a data source node for a request device.

The access network identifier of the request device may be a nodeidentifier (POP ID) of an access network of the request device. Forexample, the access network identifier of the request device may be anetwork access point identifier of user equipment (UE) in a 3rdGeneration Partnership Project (3GPP) network, may be an identifier of apacket data network gateway (PGW) of UE in a Wireless Fidelity (WiFi f)network, or may be an identifier of a WiFi access point (AP), anidentifier of a digital subscriber line access multiplexer (DSLAM), orthe like.

The processor 102 is configured to generate a first source nodesuggestion table according to the selection request message and a sourcenode selection table, where the source node selection table includes atransmission rate between the request device and at least one sourcenode. The first source node suggestion table includes an identifier ofthe at least one source node.

The source node selection table may be specifically a source nodeidentifier selection table (Source ID Selection Table), and the sourcenode selection table may be stored in the monitoring server. Thetransmission rate between the request device and the at least one sourcenode may be a transmission rate of transmitting, before this embodimentis implemented, a service the same as or similar to an IO requested bythe request device between the request device and the at least onesource node.

That the processor 102 generates a first source node suggestion tableaccording to the selection request message and a source node selectiontable may be specifically that the processor 102 selects at least onesource node from the at least one source node according to the accessnetwork identifier of the request device and the transmission ratebetween the request device and the at least one source node, so as togenerate the first source node suggestion table. The first source nodesuggestion table includes an identifier of the selected at least onesource node.

The transmitter 103 is configured to send the first source nodesuggestion table to the resolution server 104, so that the resolutionserver 104 generates a second source node suggestion table according tothe first source node suggestion table and reference information of theat least one source node and sends the second source node suggestiontable to the request device, and the request device selects a sourcenode according to the second source node suggestion table, where thereference information includes location information, status information,and load information, and a quantity of identifiers of source nodes inthe second source node suggestion table is less than or equal to aquantity of identifiers of source nodes in the first source nodesuggestion table.

The first source node suggestion table is a source node suggestion list(Suggested Source list). Because the first source node suggestion tableis generated with reference to a transmission rate between the requestdevice and each source node, the resolution server further processes thefirst source node suggestion table, so as to generate a second sourcenode suggestion table. The second source node suggestion table may bethe same as or different from the first source node suggestion table. Ifthe second source node suggestion table is the same as the first sourcenode suggestion table, a quantity of identifiers of source nodes in thesecond source node suggestion table is the same as a quantity ofidentifiers of source nodes in the first source node suggestion table;or if the second source node suggestion table is different from thefirst source node suggestion table, a quantity of identifiers of sourcenodes in the second source node suggestion table is less than a quantityof identifiers of source nodes in the first source node suggestiontable. The second source node suggestion table generated according tothe first source node suggestion table is transmitted to the requestdevice by using the resolution server, so that the request device and asource node selected by the request device can better meet atransmission requirement on a high-bandwidth service, thereby avoiding a“freeze” phenomenon caused by a low rate.

The monitoring server provided in the solution of this embodiment maygenerate a first source node suggestion table according to a selectionrequest message sent by a resolution server and a source node selectiontable, and feeds back the first source node suggestion table to theresolution server; and the resolution server processes the first sourcenode suggestion table, so as to generate a second source node suggestiontable and sends the second source node suggestion table to a requestdevice. Because the source node selection table includes a transmissionrate between the request device and at least one source node, therequest device selects a source node that better meets a transmissionbandwidth requirement of a service requested by the request device, soas to meet a transmission requirement of a high-bandwidth service andavoid a “freeze” phenomenon caused by a low transmission rate.

Embodiment 2

This embodiment further provides a monitoring server. Further, in thesolution described above, the access network identifier of the requestdevice may be obtained by the resolution server 104 according to areceived file request message sent by the request device.

Preferably, the selection request message further includes a source nodeidentifier table, and the source node identifier table is a source nodeidentifier table that is generated after the resolution server 104performs querying according to an identifier of a requested file andthat has the requested file, where the identifier of the requested fileis obtained by the resolution server 104 according to the file requestmessage.

Specifically, the source node identifier table may be a source nodeidentifier list (Sources ID List). The identifier of the requested filemay be a service identifier (Information ID) of an IO requested by therequest device.

The solution in this embodiment is based on the foregoing solution.

The processor 102 is further configured to query, according to theaccess network identifier of the request device, the source nodeselection table for a transmission rate between the access networkidentifier of the request device and each source node; and configured togenerate the first source node suggestion table according to thetransmission rate between the access network identifier of the requestdevice and each source node.

Preferably, in the monitoring server described above, the processor 102is further configured to query, according to the access networkidentifier of the request device and by means of longest prefix match,the source node selection table for the transmission rate between theaccess network identifier of the request device and each source node.

In this embodiment, based on the monitoring server in the foregoingembodiment, the receiver 101 is connected to the request device and theselected source node.

The receiver 101 is further configured to receive a transmission ratethat is between the request device and the selected source node and thatis reported by the request device or the selected source node.

The processor 102 is further configured to update the source nodeselection table according to the transmission rate between the requestdevice and the selected source node.

Preferably, the receiver 101 is further configured to receive thetransmission rate that is between the request device and the selectedsource node and that is reported by the request device or the selectedsource node according to a preset time or a preset period.

It should be noted that, the transmission rate between the requestdevice and the selected source node may be sent after the request deviceand the selected source node complete transmission of the wholerequested file, or may be sent after a part of the requested file istransmitted.

According to the monitoring server provided in the solution of thisembodiment, the processor generates a source node suggestion table, anda manner for querying a transmission rate between a particular requestdevice and each source node is provided; the receiver further updates asource node selection table in coordination with the processor, whichcan improve accuracy of the generated source node suggestion table,better ensuring a transmission rate requirement of a service having ahigh bandwidth requirement.

Embodiment 3

This embodiment provides a resolution server. FIG. 2 is a schematicstructural diagram of a resolution server according to Embodiment 3 ofthe present application. The resolution server in this embodiment islocated in an ICN network communications system. The resolution servermay be a name resolution server (NRS) and generally is implemented in ahardware manner or in a hardware and software combined manner. As shownin FIG. 2, a resolution server 200 includes a transmitter 201, areceiver 202, and a processor 203. The transmitter 201 and the receiver202 are separately connected to a monitoring server 204. The receiver202 and the processor 203 are connected to the transmitter 201. Thetransmitter 201 is further connected to a request device 205.

The transmitter 201 is configured to send a selection request message tothe monitoring server 204, so that the monitoring server 204 generates afirst source node suggestion table according to the selection requestmessage and a source node selection table, where the selection requestmessage includes an access network identifier of the request device, thesource node selection table includes a transmission rate between therequest device and at least one source node, and the first source nodesuggestion table includes an identifier of the at least one source node.

The receiver 202 is configured to receive the first source nodesuggestion table sent by the monitoring server 204.

The processor 203 is configured to generate a second source nodesuggestion table according to the first source node suggestion table andreference information of the at least one source node, where thereference information includes location information, status information,and load information, and a quantity of identifiers of source nodes inthe second source node suggestion table is less than or equal to aquantity of identifiers of source nodes in the first source nodesuggestion table.

The transmitter 201 is further configured to send the second source nodesuggestion table to the request device 205, so that the request device205 selects a source node according to the second source node suggestiontable.

The solution provided in this embodiment is a resolution servercorresponding to the foregoing monitoring server. A specificimplementation process and beneficial effects of the resolution serverare similar to those in the foregoing embodiments, and details are notdescribed herein again.

Embodiment 4

This embodiment further provides a resolution server.

In the resolution server 200, the receiver 202 is further connected tothe request device 205.

The receiver 202 is further configured to: before the transmitter 201sends the selection request message to the monitoring server 204,receive a file request message sent by the request device 205, where thefile request message includes an identifier of a requested file and theaccess network identifier of the request device.

Further, based on the foregoing resolution server,

the processor 203 is further configured to: before the transmitter sendsthe selection request message to the monitoring server 204, performquerying according to the identifier of the requested file and generatea source node identifier table having the requested file, wherecorrespondingly, the selection request message further includes thesource node identifier table.

Preferably, the transmitter 201 is further configured to send the secondsource node suggestion table to the request device 205 by using metadata(Metadata).

In the solution of this embodiment, the metadata refers to data fordescribing the second source node suggestion table, for example, astorage location of the second source node suggestion table. The secondsource node suggestion table is sent to the request device by using themetadata, implementing that the resolution server easily and efficientlymanages a large amount of networked data in the ICN network, forexample, source node suggestion tables corresponding to differentrequest devices, so that the request device can efficiently and quicklyfind the second source node suggestion table.

Based on the foregoing embodiments, the resolution server in thesolution of this embodiment can better ensure a transmission requirementof a high-bandwidth service, so that user experience can be improved.

Embodiment 5

This embodiment provides a request device. FIG. 3 is a schematicstructural diagram of a request device according to Embodiment 5 of thepresent application. As shown in FIG. 3, a request device 300 includes areceiver 301, a processor 302, and a transmitter 303. The receiver 301is connected to the processor 302, and the receiver 301 is connected tothe resolution server 304.

The receiver 301 is configured to receive a second source nodesuggestion table sent by the resolution server 304, where the secondsource node suggestion table is generated by the resolution server 304according to a first source node suggestion table and referenceinformation of at least one source node; the reference informationincludes location information, status information, and load information;the first source node suggestion table is generated by the monitoringserver according to a selection request message that is sent by theresolution server and a source node selection table; the selectionrequest message includes an access network identifier of the requestdevice; the source node selection table includes a transmission ratebetween the request device and the at least one source node; the firstsource node suggestion table includes an identifier of the at least onesource node; and a quantity of identifiers of source nodes in the secondsource node suggestion table is less than or equal to a quantity ofidentifiers of source nodes in the first source node suggestion table.

The processor 302 is configured to select a source node according to thesecond source node suggestion table.

The solution provided in this embodiment is a request devicecorresponding to the foregoing monitoring server and the foregoingresolution server. A specific implementation process and beneficialeffects of the request device are similar to those in the foregoingembodiments, and details are not described herein again.

Embodiment 6

This embodiment further provides a request device. The transmitter 303included in the request device 300 in the foregoing embodiment isfurther connected to the resolution server 304.

The transmitter 303 is configured to send a file request message to theresolution server before the receiver 301 receives the source nodesuggestion table sent by the resolution server 304, where the filerequest message includes an identifier of a requested file and theaccess network identifier of the request device.

Preferably, the receiver 301 is further configured to receive the secondsource node suggestion table that is sent by the resolution server 304by using metadata.

Based on the foregoing solution, the processor 302 is further configuredto: if the second source node suggestion table includes identifiers ofat least two source nodes, select one source node from the source nodesuggestion table according to priorities of the at least two sourcenodes, and request the requested file from the source node; orseparately request, from the at least two source nodes, contentfragments of the requested file according to priorities of the at leasttwo source nodes, to obtain the requested file.

Specifically, if the second source node suggestion table includes onlyone source node, the request device directly requests the requested filefrom the request device. The priority may be a value of the transmissionrate, and a higher rate indicates a higher priority. If the secondsource node suggestion table includes identifiers of at least two sourcenodes, and a bandwidth requirement of the requested file is relativelylow, the processor 302 can determine, according to values of priorities,a source node having a highest priority, and request the source node totransmit the requested file. However, for some services having arelatively high bandwidth transmission requirement, multiple sourcenodes may be selected according to values of priorities, to separatelyestablish connections between the request device and the multiple sourcenodes, and fragments of the requested file are transmitted, therebyimproving a rate of obtaining the requested file.

The request device provided in the solution of this embodiment canfurther select corresponding source nodes according to differentbandwidth requirements of requested files, so as to adapt to serviceshaving different transmission bandwidth requirements.

Further, the transmitter 303 is further connected to the monitoringserver.

The transmitter 303 is further configured to report a transmission ratebetween the request device and the selected source node to themonitoring server, so that the monitoring server updates the source nodeselection table.

Preferably, the transmitter 303 is further configured to report thetransmission rate between the request device and the selected sourcenode to the monitoring server according to a preset time or a presetperiod, so that the monitoring server updates the source node selectiontable.

Based on the foregoing solution, the solution in this embodiment can beadapted to services having different transmission bandwidth requirementsand the source node selection table can be regularly updated, therebyensuring accuracy of selecting a source node by the request device andbetter ensuring a transmission rate requirement of a service having ahigh bandwidth requirement.

Embodiment 7

This embodiment further provides a node selection solution. The methodmay be performed by the monitoring servers provided in the foregoingembodiments. FIG. 4 is a flowchart of a node selection method accordingto Embodiment 7 of the present application. As shown in FIG. 4, themethod specifically includes the following steps:

Step 401: Receive a selection request message sent by a resolutionserver, where the selection request message includes an access networkidentifier of a request device.

Step 402: Generate a first source node suggestion table according to theselection request message and a source node selection table.

The source node selection table includes a transmission rate between therequest device and at least one source node, and the first source nodesuggestion table includes an identifier of the at least one source node.

Step 403: Send the first source node suggestion table to the resolutionserver, so that the resolution server generates a second source nodesuggestion table according to the first source node suggestion table andreference information of the at least one source node and sends thesecond source node suggestion table to the request device, and therequest device selects a source node according to the second source nodesuggestion table.

The reference information includes location information, statusinformation, and load information. A quantity of identifiers of sourcenodes in the second source node suggestion table is less than or equalto a quantity of identifiers of source nodes in the first source nodesuggestion table.

In the foregoing solution, the access network identifier of the requestdevice is obtained by the resolution server according to a received filerequest message sent by the request device.

Further, based on the foregoing solution, the selection request messagefurther includes a source node identifier table, and the source nodeidentifier table is a source node identifier table that is generatedafter the resolution server performs querying according to an identifierof a requested file and that has the requested file, where theidentifier of the requested file is obtained by the resolution serveraccording to the file request message.

Further, the foregoing step 402 of generating a first source nodesuggestion table according to the selection request message and a sourcenode selection table specifically includes:

querying, according to the access network identifier of the requestdevice, the source node selection table for a transmission rate betweenthe access network identifier of the request device and each sourcenode; and

generating the first source node suggestion table according to thetransmission rate between the access network identifier of the requestdevice and each source node.

As described above, the querying, according to the access networkidentifier of the request device, the source node selection table for atransmission rate between the access network identifier of the requestdevice and each source node specifically includes:

querying, according to the access network identifier of the requestdevice and by means of longest prefix match, the source node selectiontable for the transmission rate between the access network identifier ofthe request device and each source node.

Based on the solution of the embodiment described above, the nodeselection method further includes:

receiving a transmission rate that is between the request device and theselected source node and that is reported by the request device or theselected source node, and updating the source node selection table.

Preferably, the receiving a transmission rate that is between therequest device and the selected source node and that is reported by therequest device or the selected source node, and updating the source nodeselection table specifically includes:

receiving the transmission rate that is between the request device andthe selected source node and that is reported by the request device orthe selected source node according to a preset time or a preset period,and updating the source node selection table.

The node selection method in this embodiment may be performed by themonitoring server provided in the foregoing embodiment. A specificimplementation process and beneficial effects of the node selectionmethod are similar to those in the foregoing embodiments, and detailsare not described herein again.

Embodiment 8

This embodiment further provides a node selection method. The method maybe performed by the resolution server provided in the foregoingembodiment. FIG. 5 is a flowchart of a node selection method accordingto Embodiment 8 of the present application. As shown in FIG. 5, themethod specifically includes the following steps:

Step 501: Send a selection request message to a monitoring server, sothat the monitoring server generates a first source node suggestiontable according to the selection request message and a source nodeselection table.

The selection request includes an access network identifier of a requestdevice, the source node selection table includes a transmission ratebetween the request device and at least one source node, and the firstsource node suggestion table includes an identifier of the at least onesource node.

Step 502: Receive the first source node suggestion table sent by themonitoring server.

Step 503: Generate a second source node suggestion table according tothe first source node suggestion table and reference information of theat least one source node.

The reference information includes location information, statusinformation, and load information. A quantity of identifiers of sourcenodes in the second source node suggestion table is less than or equalto a quantity of identifiers of source nodes in the first source nodesuggestion table.

Step 504: Send the second source node suggestion table to the requestdevice, so that the request device selects a source node according tothe second source node suggestion table.

Further, before step 501 of sending a selection request message to amonitoring server in the foregoing solution, the method furtherincludes:

receiving a file request message sent by the request device, where thefile request message includes an identifier of a requested file and theaccess network identifier of the request device.

Based on the foregoing solution, before step 501 of sending a selectionrequest message to a monitoring server, the method further includes:

performing querying according to the identifier of the requested fileand generating a source node identifier table having the requested file,where correspondingly, the selection request message further includesthe source node identifier table.

Preferably, step 503 of sending the second source node suggestion tableto the request device in the foregoing solution specifically includes:

sending the second source node suggestion table to the request device byusing metadata.

The node selection method in this embodiment may be performed by theresolution server provided in the foregoing embodiment. A specificimplementation process and beneficial effects of the node selectionmethod are similar to those in the foregoing embodiment, and details arenot described herein again.

Embodiment 9

This embodiment further provides a node selection method. The method maybe performed by the request device provided in the foregoing embodiment.FIG. 6 is a flowchart of a node selection method according to Embodiment9 of the present application. As shown in FIG. 6, the methodspecifically includes the following steps:

Step 601: Receive a second source node suggestion table sent by aresolution server.

The second source node suggestion table is generated by the resolutionserver according to a first source node suggestion table and referenceinformation of at least one source node; the reference informationincludes location information, status information, and load information;the first source node suggestion table is generated by the monitoringserver according to a selection request message that is sent by theresolution server and a source node selection table; the selectionrequest includes an access network identifier of the request device; thesource node selection table includes a transmission rate between therequest device and the at least one source node; the first source nodesuggestion table includes an identifier of the at least one source node;and a quantity of identifiers of source nodes in the second source nodesuggestion table is less than or equal to a quantity of identifiers ofsource nodes in the first source node suggestion table.

Step 602: Select a source node according to the second source nodesuggestion table.

Further, before step 601 of receiving a second source node suggestiontable sent by a resolution server in the foregoing solution, the methodfurther includes:

sending a file request message to the resolution server, where the filerequest message includes an identifier of a requested file and theaccess network identifier of the request device.

Further, step 601 of receiving a second source node suggestion tablesent by a resolution server in the foregoing solution specificallyincludes:

receiving the second source node suggestion table that is sent by theresolution server by using metadata.

Preferably, the foregoing step 602 of selecting a source node accordingto the second source node suggestion table specifically includes:

if the second source node suggestion table includes identifiers of atleast two source nodes, selecting one source node from the source nodesuggestion table according to priorities of the at least two sourcenodes, and requesting the requested file from the source node; or

separately requesting, from the at least two source nodes, contentfragments of the requested file according to priorities of the at leasttwo source nodes, to obtain the requested file.

Further, the foregoing solution further includes:

reporting a transmission rate between the request device and theselected source node to the monitoring server, so that the monitoringserver updates the source node selection table.

In the foregoing solution, the reporting a transmission rate between therequest device and the selected source node to the monitoring server andupdating the source node selection table specifically includes:

reporting the transmission rate between the request device and theselected source node to the monitoring server according to a preset timeor a preset period, so that the monitoring server updates the sourcenode selection table.

The node selection method in this embodiment may be performed by therequest device provided in the foregoing embodiment. A specificimplementation process and beneficial effects of the node selectionmethod are similar to those in the foregoing embodiment, and details arenot described herein again.

Embodiment 10

This embodiment further provides a node selection method. FIG. 7 is aflowchart of a node selection method according to Embodiment 10 of thepresent application. This embodiment is illustrated by using a specificexample. The method is performed by a resolution server, a monitoringserver, a request device, and a source node that is selected by therequest device in an interactive manner. As shown in FIG. 7, the methodincludes:

Step 701: A request device sends a file Request message to a resolutionserver, where the file Request message includes an Information ID and aPoP ID1.

The Information ID is an identifier of a requested information object,and the PoP ID1 is an access network identifier of the request device.

Step 702: The resolution server generates a Sources ID List according tothe Information ID in the file Request message.

Step 703: The resolution server sends a Source ID selection Requestmessage to a monitoring server, where the Source ID selection Requestmessage includes the Sources ID List and the PoP ID1.

Step 704: The monitoring server queries, according to the PoP ID1, theSource ID Selection Table for a transmission rate between the PoP ID1and each Source ID.

It should be noted that, before step 704 is performed, the monitoringserver has created and generated the Source ID Selection Table. TheSource ID Selection Table includes at least a PoP ID, all Source IDs, acorresponding transmission rate (Transmission Rate) between the PoP ID1and each Source ID, and a statistical time (Time) of the transmissionrate. The transmission rate may be specifically an average bitrate(Average Bitrate).

It should be noted that, while the Source ID Selection Table is queriedaccording to the PoP ID1 to obtain the transmission rate between the PoPID1 and each Source ID, a current time also needs to be considered. Ifthere is no time segment corresponding to the current time, atransmission rate between the PoP ID1 and each Source ID within anadjacent time segment is selected.

The Source ID Selection Table may be as shown in Table 1 below.

TABLE 1 PoP ID Source ID Average Bitrate PoP ID 1 Source1 ID 1000 kbpsPoP ID 1 Source2 ID 2000 kbps PoP ID 1 Source3 ID 1500 kbps PoP ID 2Source1 ID  800 kbps PoP ID 3 Source2 ID 2000 kbps PoP ID 4 Source3 ID1500 kbps

Referring to Table 1, the monitoring server queries the Source IDSelection Table according to the PoP ID1 to obtain transmission ratesbetween the PoP ID1 and a Source1 ID, a Source2 ID, and a Source3 ID.

Step 705: The monitoring server generates a Suggested Source ID List1according to transmission rates between the PoP ID1 and the Source1 ID,the Source2 ID, and the Source3 ID.

The Suggested Source ID List1 includes the following identifierinformation: the Source1 ID, the Source2 ID, and the Source3 ID. Indescending order of priorities, the Source IDs are sorted as follows:the Source2 ID, the Source3 ID, and the Source1 ID.

Step 706: The monitoring server sends the Suggested Source ID List1 tothe resolution server by using a Source ID Selection Response message.

Step 707: The resolution server generates a Suggested Source ID List2according to the Suggested Source ID List1 and reference information ofa Source1, Source2, and Source3.

The reference information may be location information, statusinformation, and load information of the Source1, the Source2, and theSource3. In this embodiment, the Suggested Source ID List1 is the sameas the Suggested Source ID List2, that is, both the Suggested Source IDList1 and the Suggested Source ID List2 include the following identifierinformation: the Source1 ID, the Source2 ID, and the Source3 ID.

Step 708: Send metadata of the Suggested Source ID List2 to the requestdevice.

Step 709 a: The request device reads the Suggested Source ID List2corresponding to the metadata, and sends a first segment request messageto the Source1 ID according to a priority of each Source ID in theSuggested Source ID List2.

Step 709 b: The request device sends a second segment request message tothe Source2 ID.

Step 709 c: The request device sends a third segment request message tothe Source3 ID.

It should be noted that, there is no definite time sequence relationshipamong steps 908 a to 908 c, and steps 908 a to 908 c may besimultaneously performed, or may be performed sequentially.

Step 710 a: The request device receives a first content fragment sent bythe Source1 ID.

Step 710 b: The request device receives a second content fragment sentby the Source2 ID.

Step 710 c: The request device receives a third content fragment sent bythe Source3 ID.

The request device may be connected to source nodes respectivelycorresponding to the Source1 ID, the Source2 ID, and the Source3 ID, sothat corresponding content fragments are transmitted. The contentfragments corresponding to the three different source nodes may beclassified according to priorities of the three source nodes.

It should be noted that, during or after transmission, the Source1 ID,the Source2 ID, the Source3 ID, and the request device may further sendtransmission rates corresponding to the Source1 ID, the Source2 ID, theSource3 ID, and the request device to the monitoring server, so as toupdate the Source ID Selection Table.

The solution in this embodiment illustrates the methods in the foregoingembodiments by using a specific example. Beneficial effects of thesolution in this embodiment are similar to those in the foregoingembodiments, and details are not described herein again.

Persons of ordinary skill in the art may understand that all or some ofthe steps of the method embodiments may be implemented by a programinstructing relevant hardware. The program may be stored in acomputer-readable storage medium. When the program runs, the steps ofthe method embodiments are performed. The foregoing storage mediumincludes: any medium that can store program code, such as a ROM, a RAM,a magnetic disk, or an optical disc.

Finally, it should be noted that the foregoing embodiments are merelyintended for describing the technical solutions of the presentapplication, but not for limiting the present application. Although thepresent application is described in detail with reference to theforegoing embodiments, persons of ordinary skill in the art shouldunderstand that they may still make modifications to the technicalsolutions described in the foregoing embodiments or make equivalentreplacements to some or all technical features thereof, withoutdeparting from the scope of the technical solutions of the embodimentsof the present application.

What is claimed is:
 1. A monitoring server, comprising: a receiver; aprocessor; and a transmitter, wherein the receiver, the processor, andthe transmitter are sequentially connected, and the receiver and thetransmitter are connected to a resolution server; the receiver isconfigured to receive a selection request message sent by the resolutionserver, wherein the selection request message comprises an accessnetwork identifier of a request device; the processor is configured togenerate a first source node suggestion table according to the selectionrequest message and a source node selection table, wherein the sourcenode selection table comprises a transmission rate between the requestdevice and at least one source node, and the first source nodesuggestion table comprises an identifier of the at least one sourcenode; and the transmitter is configured to send the first source nodesuggestion table to the resolution server, so that the resolution servergenerates a second source node suggestion table according to the firstsource node suggestion table and reference information of the at leastone source node and sends the second source node suggestion table to therequest device, and the request device selects a source node accordingto the second source node suggestion table, wherein the referenceinformation comprises location information, status information, and loadinformation, and a quantity of identifiers of source nodes in the secondsource node suggestion table is less than or equal to a quantity ofidentifiers of source nodes in the first source node suggestion table.2. The monitoring server according to claim 1, wherein the accessnetwork identifier of the request device is obtained by the resolutionserver according to a received file request message sent by the requestdevice.
 3. The monitoring server according to claim 2, wherein theselection request message further comprises a source node identifiertable, and the source node identifier table is a source node identifiertable that is generated after the resolution server performs queryingaccording to an identifier of a requested file and that includes theidentifier of the at least one source node which has the requested file,wherein the identifier of the requested file is obtained by theresolution server according to the file request message.
 4. Themonitoring server according to claim 1, wherein the processor is furtherconfigured to query, according to the access network identifier of therequest device, the source node selection table for a transmission ratebetween the access network identifier of the request device and eachsource node, and generate the first source node suggestion tableaccording to the transmission rate between the access network identifierof the request device and each source node.
 5. The monitoring serveraccording to claim 4, wherein the processor is further configured toquery, according to the access network identifier of the request deviceand by means of longest prefix match, the source node selection tablefor the transmission rate between the access network identifier of therequest device and each source node.
 6. The monitoring server accordingto claim 1, wherein the receiver is further connected to the requestdevice and the selected source node; the receiver is further configuredto receive a transmission rate that is between the request device andthe selected source node and that is reported by the request device orthe selected source node; and the processor is further configured toupdate the source node selection table according to the transmissionrate between the request device and the selected source node.
 7. Themonitoring server according to claim 6, wherein the receiver is furtherconfigured to receive the transmission rate that is between the requestdevice and the selected source node and that is reported by the requestdevice or the selected source node according to a preset time or apreset period.
 8. A resolution server, comprising: a transmitter; areceiver; and a processor, wherein the receiver and the processor areconnected to the transmitter; the transmitter and the receiver areseparately connected to a monitoring server; and the transmitter isfurther connected to a request device; the transmitter is configured tosend a selection request message to the monitoring server, so that themonitoring server generates a first source node suggestion tableaccording to the selection request message and a source node selectiontable, wherein the selection request message comprises an access networkidentifier of the request device, the source node selection tablecomprises a transmission rate between the request device and at leastone source node, and the first source node suggestion table comprises anidentifier of the at least one source node; the receiver is configuredto receive the first source node suggestion table sent by the monitoringserver; the processor is configured to generate a second source nodesuggestion table according to the first source node suggestion table andreference information of the at least one source node, wherein thereference information comprises location information, statusinformation, and load information, and a quantity of identifiers ofsource nodes in the second source node suggestion table is less than orequal to a quantity of identifiers of source nodes in the first sourcenode suggestion table; and the transmitter is further configured to sendthe second source node suggestion table to the request device, so thatthe request device selects a source node according to the second sourcenode suggestion table.
 9. The resolution server according to claim 8,wherein the receiver is further connected to the request device; and thereceiver is further configured to: before the transmitter sends theselection request message to the monitoring server, receive a filerequest message sent by the request device, wherein the file requestmessage comprises an identifier of a requested file and the accessnetwork identifier of the request device.
 10. The resolution serveraccording to claim 9, wherein the processor is further configured to:before the transmitter sends the selection request message to themonitoring server, perform querying according to the identifier of therequested file and generate a source node identifier table having therequested file, wherein correspondingly, the selection request messagefurther comprises the source node identifier table.
 11. The resolutionserver according to claim 8, wherein the transmitter is furtherconfigured to send the second source node suggestion table to therequest device by using metadata.
 12. A request device, comprising: areceiver; a processor; and a transmitter, wherein the receiver isconnected to the processor, and the receiver is further connected to aresolution server; the receiver is configured to receive a second sourcenode suggestion table sent by the resolution server, wherein the secondsource node suggestion table is generated by the resolution serveraccording to a first source node suggestion table and referenceinformation of at least one source node; the reference informationcomprises location information, status information, and loadinformation; the first source node suggestion table is generated by themonitoring server according to a selection request message that is sentby the resolution server and a source node selection table; theselection request message comprises an access network identifier of therequest device; the source node selection table comprises a transmissionrate between the request device and the at least one source node; thefirst source node suggestion table comprises an identifier of the atleast one source node; and a quantity of identifiers of source nodes inthe second source node suggestion table is less than or equal to aquantity of identifiers of source nodes in the first source nodesuggestion table; and the processor is configured to select a sourcenode according to the second source node suggestion table.
 13. Therequest device according to claim 12, wherein the transmitter isconfigured to send a file request message to the resolution serverbefore the receiver receives the second source node recommendation tablesent by the resolution server, wherein the file request messagecomprises an identifier of a requested file and the access networkidentifier of the request device.
 14. The request device according toclaim 12, wherein the receiver is further configured to receive thesecond source node suggestion table that is sent by the resolutionserver by using metadata.
 15. The request device according to claim 12,wherein the processor is further configured to: if the second sourcenode suggestion table comprises identifiers of at least two sourcenodes, select one source node from the source node suggestion tableaccording to priorities of the at least two source nodes, and requestthe requested file from the source node; or separately request, from theat least two source nodes, content fragments of the requested fileaccording to priorities of the at least two source nodes, to obtain therequested file.
 16. The request device according to claim 12, whereinthe transmitter is further connected to the monitoring server; and thetransmitter is further configured to report a transmission rate betweenthe request device and the selected source node to the monitoringserver, so that the monitoring server updates the source node selectiontable.
 17. The request device according to claim 16, wherein thetransmitter is further configured to report the transmission ratebetween the request device and the selected source node to themonitoring server according to a preset time or a preset period, so thatthe monitoring server updates the source node selection table.